You, the crab, go away for a while after your big meal, and the snails have a chance to reproduce. Stop the model by clicking the STOP button (the square button in the Controls panel). Then allow the snails to reproduce by clicking the REPRODUCE button. Each of the surviving snails generates two new snails by cloning, then dies. Unlike with most real snails, there is no mating. Each offspring is identical to its parent. To see this, switch back to the SELECT tool (the standard arrow button in the Tools panel) and double-click on a few pairs of nearby snails (twin children of a single parent). You should see that the shell thickness is the same in both snails in each pair. [ 10 ] You are hungry again! Start the simulation by clicking the GO button, click on the CLAW tool so you can eat again, and have another meal of 25 snails. Dont forget to try to keep your CRAB HAPPINESS SCORE high by eating your snails with the fewest clicks possible. [ 11 ] Digest your meal and let the snails reproduce again by clicking on the REPRODUCE button. Then have one more meal of 25 snails. Yum! At the end, REPRODUCE once more so you finish with about 50 snails. SimBio Virtual Labs | Darwinian Snails 2016, SimBio. All Rights Reserved. 7 [ 12 ] When your third meal is done, copy the histogram of shell thicknesses and paste it into your text document. Label it Exercise 1: Generation 4. (Remember, to copy a histogram, mouse over the center of the histogram, right-click (Windows) or Control-click (OSX), and select Copy View. Then use the paste command to place the screen shot in your word processing document.) [ 12.1 ] Compare the starting histogram you saved earlier to this fourth-generation histogram. Has the distribution of shell thicknesses changed as you predicted in Step 4